I'm on the other side in that I have owned retail business' and franchises.
My franchisor, and I assume most others engage the help of a professional leasing agent to negotiate on their behalf. I know the guy that looks after ours ( or is supposed to) also looks after Bakers Delight and one other franchise that I forget atm.
Thats his fulltime job, he also sources new sites for franchises. Its a bit of a boys club, AMP, QIC, Lendlease, Stocklands, all the leasing guys know each other and the leasing agents.